This invention relates to devices, or apparatuses for dispensing wire from substantially cylindrical or tubular containment structure. This invention also relates to wire containing or transporting apparatuses or carriers where the wire has a tendency to migrate from the apparatus during shipping or handling. More particularly, in a preferred practice, the present invention relates to apparatuses and methods for containing and dispensing a specific type of wire namely, a guidewire. This invention is particularly applicable to the process of guidewire containment in dispenser assemblies where the guidewire has a slippery coating thereon.
Guidewires have been described in a number of patents, representative examples of which are U.S. Pat. No. 4,545,390 to Leary, U.S. Pat. No. 3,973,556 to Fleischhacker et al., and U.S. Pat. No. 4,538,622 to Samson et al. Guidewires have many different structural features and configurations depending upon the medical procedure with which they are to be used. Generally speaking, guidewires are used in the process of directing a catheter to identified locations or sites within a patient's cardiovascular or peripheral vascular system for the purpose of diagnosis or treatment. Typically, the guidewire is placed percutaneously into a patient's blood vessel and is directed to the previously identified site. A catheter selected to provide the particular medical procedure at the site then is advanced over the guidewire until the functional structure, working or operating portion of the catheter is located in the proximity of the previously identified site. The catheter then is utilized to accomplish the selected medical procedure. The guidewire may be withdrawn from the vascular system before, during, or after utilization of the catheter.
A typical example of the above process would be to utilize a guidewire to direct an angiographic catheter to a site of a vascular obstruction. Thereafter an angioplasty procedure, e.g., balloon angioplasty, may be carried out by means of, e.g., a balloon angioplasty catheter. Other catheters are designed to perform procedures such as application of ultrasound to an obstruction, delivery of drugs, execution of diagnostic procedures, or any of a number of applications of drugs, energy or other forces within the body.
The present invention is intended to be used with essentially all guidewires. However, guidewires are often coated with a slippery or hydrophilic coating to make the processes of passing a guidewire through a body vessel and passing a catheter over the guidewire proceed more easily. This invention is particularly applicable to the containment, transportation, and dispensing of coated guidewires in the dispenser assembly until they are used in a medical procedure.
The present invention, in a preferred embodiment, is particularly applicable to insertion and utilization of guidewires having predetermined, or preferential distal end configurations other than straight or linear. The distal ends of such guidewires would have a built-in preference, bias, or memory which causes their distal ends to assume (or to resume) a curved, angled, or bent configuration if they are not physically restrained to a straight or linear configuration. For example, some guidewires have what is referred to as a "J" distal end configuration. Guidewires with a "J" distal end configuration, after being inserted into the vasculature in a straight configuration (e.g., held in a linear arrangement by means of a straightener), return to their "J" configuration after the straightening device is withdrawn. When such a guidewire is steered into the vascular system, the rounded bottom of the "J" (as opposed to the tip of the "J") is at the very distal or leading end of the guidewire. In this manner, "J" configuration guidewires present a potentially less traumatic, rounded configuration to the vascular system through which the guidewire passes.
For reasons of device protection, ease of handling and dispensing, and fluid flushing, guidewires tend to be stored and transported in tubular dispenser assemblies, carriers, or containers. Generally speaking, the tubular dispenser assembly or loop of tubing will have a substantially larger inside diameter than the outside diameter of a guidewire contained therein. To utilize a guidewire contained within such an assembly in a medical procedure, the guidewire must be partially and ultimately, totally removed therefrom.
During the transportation and handling of guidewires contained within a shipping or dispenser assembly, a problem has sometimes developed in that guidewires tend to migrate or to emerge from the dispenser in a less than controlled fashion. The guidewire, which may be from 20 to 400 cm in length (or longer), is sufficiently longitudinally rigid so as to have a natural tendency to migrate from its dispenser.
Also, medical personnel handling the guidewire under sterile or near sterile operative conditions must be able to control, as precisely as possible, dispensing of the guidewire. With guidewire handling problems resulting from medical personnel wearing surgical gloves and a guidewire coated with a slippery, hydrophilic coating, exact containment and dispensing of the device can be very important to reducing the duration and increasing the overall success of the medical procedure in which the guidewire is used.
One approach to the above problem has been simply to provide a vinyl, restriction fit cap which fits the open, dispensing end of a tubular guidewire dispenser. This approach has the potential drawback of not being applicable for transportation/storage of guidewires having a so-called "J" distal end. Capped "J" guidewires would require a separate, additional straightener assembly to straighten the "J" guidewire configuration during initial guidewire insertion. In other words, the capped dispenser approach would not likely be applicable to contain guidewires having a non-linear distal end predisposition.